A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Adsorption behaviors and atomistic mechanisms of iodate and iodide on hollow spherical allophane nanoparticles
Abstract The adsorption of radioactive iodate (IO3 −) and iodide (I−) anions on natural minerals is critical for nuclear environmental safety. Allophane, a nanosized clay mineral, is considered to adsorb IO3 − and I−, but the essential interactions between both anions and allophane remain unknown, due to the challenges of characterizing extremely small allophane nanoparticles in complex soils and obtaining high-purity natural allophane. In this work, neat allophane (Allo) nanoparticles were synthesized and used to study their adsorption for IO3 − and I− anions. The adsorption kinetics, adsorption thermodynamics, pH-dependent adsorption-desorption, and competitive adsorption (Cl− and SO4 2−) were quantitatively investigated. Moreover, combined with advanced spectroscopic analyses of X-ray absorption fine structure (XAFS) and X-ray photoelectron spectroscopy (XPS), the atomistic adsorption mechanisms were illustrated. The adsorption capacities of Allo can be about 0.22 mmol/g for IO3 − and 0.077 mmol/g for I−, which are at least one order of magnitude and 2.6-fold higher than those of other clay minerals, respectively. The IO3 − adsorption involved the ligand exchange and electrostatic attraction interactions, while the I− adsorption involved the Lewis acid-base and hydrogen-bond interactions. The inner-sphere adsorption mainly occurred in the wedge-shaped nanopores within Allo. The findings will improve the understanding of IO3 − and I− adsorption on allophane, promote the practical applications of natural allophane in the management of nuclear wastes, and provide foundations for revealing the geochemical behaviors of iodine.
Graphical abstract Display Omitted
Highlights Allophane (Allo) has high adsorption capacities to I− and particularly IO3 −. Adsorption behaviors of IO3 − and I− on Allo were quantitatively evaluated. Firstly revealing the local chemical environments of adsorbed iodine on Allo surface. Illustrating multiple surface-interface interactions between Allo and IO3 −/I− at an atomistic scale.
Adsorption behaviors and atomistic mechanisms of iodate and iodide on hollow spherical allophane nanoparticles
Abstract The adsorption of radioactive iodate (IO3 −) and iodide (I−) anions on natural minerals is critical for nuclear environmental safety. Allophane, a nanosized clay mineral, is considered to adsorb IO3 − and I−, but the essential interactions between both anions and allophane remain unknown, due to the challenges of characterizing extremely small allophane nanoparticles in complex soils and obtaining high-purity natural allophane. In this work, neat allophane (Allo) nanoparticles were synthesized and used to study their adsorption for IO3 − and I− anions. The adsorption kinetics, adsorption thermodynamics, pH-dependent adsorption-desorption, and competitive adsorption (Cl− and SO4 2−) were quantitatively investigated. Moreover, combined with advanced spectroscopic analyses of X-ray absorption fine structure (XAFS) and X-ray photoelectron spectroscopy (XPS), the atomistic adsorption mechanisms were illustrated. The adsorption capacities of Allo can be about 0.22 mmol/g for IO3 − and 0.077 mmol/g for I−, which are at least one order of magnitude and 2.6-fold higher than those of other clay minerals, respectively. The IO3 − adsorption involved the ligand exchange and electrostatic attraction interactions, while the I− adsorption involved the Lewis acid-base and hydrogen-bond interactions. The inner-sphere adsorption mainly occurred in the wedge-shaped nanopores within Allo. The findings will improve the understanding of IO3 − and I− adsorption on allophane, promote the practical applications of natural allophane in the management of nuclear wastes, and provide foundations for revealing the geochemical behaviors of iodine.
Graphical abstract Display Omitted
Highlights Allophane (Allo) has high adsorption capacities to I− and particularly IO3 −. Adsorption behaviors of IO3 − and I− on Allo were quantitatively evaluated. Firstly revealing the local chemical environments of adsorbed iodine on Allo surface. Illustrating multiple surface-interface interactions between Allo and IO3 −/I− at an atomistic scale.
Adsorption behaviors and atomistic mechanisms of iodate and iodide on hollow spherical allophane nanoparticles
Wang, Shun (author) / Zhang, Yanjun (author) / Liu, Dong (author) / Yuan, Peng (author) / Li, Mengyuan (author) / Du, Peixin (author) / Zhao, Jinkui (author) / Yu, Wenbin (author) / Wang, Howard (author)
Applied Clay Science ; 250
2024-02-07
Article (Journal)
Electronic Resource
English
Synthesis and adsorption characteristics of hollow spherical allophane nano-particles
| Online Contents | 2012
DNA adsorption characteristics of hollow spherule allophane nano-particles
| British Library Online Contents | 2013
Adsorption of iodide and iodate on colloidal silver surface
| British Library Online Contents | 2008